feat(cockpit): add alloy config snippet generation for metrics, logs and traces

[jremy42]

close #5498

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Relates OR Closes #0000

Release note for CHANGELOG:

[codecov-commenter]

Codecov Report

❌ Patch coverage is 43.75000% with 63 lines in your changes missing coverage. Please review.
✅ Project coverage is 50.64%. Comparing base (6104780) to head (f5fb495).
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
...nternal/namespaces/cockpit/v1/custom_config_get.go	0.00%	42 Missing ⚠️
...ernal/namespaces/cockpit/v1/custom_config_alloy.go	67.92%	13 Missing and 4 partials ⚠️
...spaces/cockpit/v1/custom_config_alloy_templates.go	76.47%	2 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5638      +/-   ##
==========================================
- Coverage   50.65%   50.64%   -0.01%     
==========================================
  Files         340      342       +2     
  Lines       78127    78238     +111     
==========================================
+ Hits        39577    39626      +49     
- Misses      37054    37110      +56     
- Partials     1496     1502       +6     

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[remyleone]

I would strongly prefer having a template file that could be rendered and with a proper type comment